docs: def timestring(self, pattern="%Y-%m-%d %H:%M:%S", timezone=None):
          """Returns a time string.
  
          :param pattern = "%Y-%m-%d %H:%M:%S"
              The format used. By default, an ISO-type format is used. The
              syntax here is identical to the one used by time.strftime() and
              time.strptime().
  
          :param timezone = self.timezone
              The timezone (in seconds west of UTC) to return the value in. By
              default, the timezone used when constructing the class is used
              (local one by default). To use UTC, use timezone = 0. To use the
              local tz, use timezone = chronyk.LOCALTZ.
          """
          if timezone is None:
              timezone = self.timezone
          timestamp = self.__timestamp__ - timezone
          timestamp -= LOCALTZ
          return _strftime(pattern, _gmtime(timestamp))